Bis(haloalkyl)methoxymethane phosphonates

ABSTRACT

WHEREIN R1 AND R2 EACH IS AN ALKYL RADICAL CONTAINING 2, 3 OR 4 CARBON ATOMS SUBSTITUTED AT POSITION 2 WITH AT LEAST ONE ATOM OF BROMINE OR CHLORINE.   H3C-O-CH2-P(=O)(-O-R1)-O-R2   1. ESTERS OF METHOXYMETHANEPHOSPHONIC ACID OF THE GENERAL FORMULA

United States Patent M 3,851,020 BIS(HALOALKYL)METHOXYMETHANEPHOSPHONATES Daniel Balde, Levallois Ferret, and Georges Nagy,Moutrouge, France, assignors to Produits Chimiques Ugine Kuhlmaun,Paris, France No Drawing. Filed July 7, 1972, Ser. No. 269,620 Claimspriority, application France, July 15, 1971, 7125823 Int. Cl. C07f 9/40US. Cl. 260950 4 Claims ABSTRACT OF THE DISCLOSURE This inventionrelates to esters of methoxymethanephosphonic acid of the generalformula CH3-O-CH2P wherein R and R each is an alkyl radical containing2, 3 or 4 carbon atoms substituted at position 2 with at least one atomof bromine or chlorine.

The esters of methoxymethanephosphonic acid of this invention can beused as ignifugation agents and are useful for phytopharmaceuticalapplications and as intermediates.

BACKGROUND OF THE INVENTION I. Field of the Invention This inventionrelates to esters of methoxymethanephosphonic acid.

II. Description of the Prior Art The compounds of the invention hereincan be prepared by a number of well known and conventional reactios. Forexample, chloromethylmethylether can be condensed with an alkaline metalsalt of the corresponding secondary phosphite according to theMichaelis-Becker reaction.

SUMMARY OF THE INVENTION This invention relates to esters ofmethoxymethanephosphonic acid of the general formula /0 R /0 R CH-O-CHzCl P O R; CHa-O-OHr-P R301 CR 0 OR:

wherein R the same or different from R and R is an alkyl radical of 2, 3or 4 carbon atoms substituted at position 2 with a bromine or chlorineatom. R and R each have the above-defined meaning.

3,851,020 Patented Nov. 26, 1974 DESCRIPTION OF THE PREFERREDEMBODIMENTS The trialkyl phosphites which are useful for preparing thecompounds of this invention are obtained by the addition of 1,2-alkyleneoxides to a phosphorus trihalide such as phosphorus trichloride,phosphorus tribromide or a mixture of phosphorus trihalides. If a singlealkylene oxide is reacted with the phosphorus derivative, phosphitespossessing the identical alkyl radical are obtained. If a mixture ofdifferent alkylene oxides are reacted, the mixed end-products areobtained wherein R R and R are different according to the combinationswhich are possible. In this case, it is advantageous to add thedifferent alkylene oxides, one after the other, in order to obtainbetter defined end-products.

The following examples are illustrative of the preparation of esters ofmethoxymethanephosphonic acid according to this invention.

Example 1 269.5 gm. of tris (2-chloroethyl) phosphite (1 mole) preparedby the addition of 132 gm. of ethylene oxide (3 moles) to 137.5 gm. ofphosphorus trichloride (1 mole) were placed in a flask. The temperaturewas increased to 100 C. and 85 gm. of chloromethylmethylether (1.05moles) were added to the flask over a period of thirty minutes. Afterthe addition of the ether, the heating of the reaction medium wascontinued for about 5 hours. The 1,2-dichloroethane which formed wasdistilled and 250 gm. of crude bis(2-chloroethyl)methoxymethanephosphonate having the formula were recovered.

This crude product which contained about 10% of the rearrangementproduct of the phosphite, bis(2-chloroethyl)-2-chloroethylphosphonate,could be used as such for certain applications. The crude product was,however, subjected to distillation under reduced pressure (130 C./ 0.2mm. Hg) to provide a yield of 85% by comparison to the startingphosphite, of a product having the following elemental composition:

C, 28.6% (theoretical amount 28.7%) H, 5.1% (theoretical amount 5.2%)

O, 25.3% (theoretical amount 25.5%) P, 12.2% (theoretical amount 12.35%)Cl, 28.8 (theoretical amount 283%) Analysis by nuclear magneticresonance showed the product to be substantially pure bis(2-chloroethyl)methoxymethanephosphonate having an index of refraction 25 20 n 1.4678and a. density d .-=1.3484.

Example 2 311.5 gm. of tris(2-chloroisopropyl) phosphite (1 mole)prepared by the addition of 174 gm. of propylene oxide (3 moles) to137.5 gm. of phosphorus trichloride (1 mole) were placed in a flask. Thetemperature was increased to C. and 85 gm. chloromethylmethylether (1.05moles) were added to the flask over a period of 1%. hours. After theaddition of the ether, the temperature was maintained at 100 C. forabout six hours and thereafter, gm. of 1,2-dichloropropane which formedwas recovered by distillation.

275 gm. of crude bis(Z-chloroisopropyl) methoxymethanephosphonate havingthe formula containing about of the rearrangement product of thephosphite, bis(2-chloroisopropyl) 2-chloroisopropylphosphonate, wererecovered, The crude product was subjected to distillation under reducedpressure (130 C./ 0.2 mm. Hg) providing a yield of about 90% bycomparison to the starting phosphite, of a product having the followingelemental composition:

C, 34.1% (theoretical amount 34.4%) H, 6.1% (theoretical amount 6.1%) O,22.8% (theoretical amount 23.0)

P, 11.0% (theoretical amount 11.1% Cl, 26.0% (theoretical amount 25.4%)

Analysis by nuclear magnetic resonance showed the product to besubstantially pure bis(Z-chloroisopropyl) methoxymethanephosphonatehaving an index of refraction of 20 11 -14608 and a density d =1.2547.

Example 3 415 gm. of tris(1,3-dichloroisopropyl) phosphite (1 mole) wereplaced in a flask. The temperature was increased to 100 C. and 85 gm. ofchloromethylmethylether (1.05 moles) were added to the flask over aperiod of 1 hour. After the addition of reactant, the temperature wasmaintained at 100 C. for seven hours followed by vacuum distillation of145 gm. 1,2,3-trichloropropane.

344 gm. of crude bis(1,3-dichloroisopropyl) methoxymethanephosphonatehaving the formula 011.01 I' CHz-OCHr-POCH\ 8 L CHzCl containingapproximately of the rearrangement product of the phosphite,bis(1,3-dichloroisopropyl) 1,3- dichloroisopropylphosphonate, wererecovered.

Following distillation under reduced pressure (150 C./ 0.5 mm. Hg), aproduct was recovered at a yield of about 80% of the starting phosphitehaving the following elemental composition:

C, 27.5% (theoretical amount 27.6%) H, 4.25% (theoretical amount 4.3%)O, 18.2% (theoretical amount 18.4%) P, 8.85% (theoretical amount 8.9%)CI, 41.2% (theoretical amount 40.8%)

Analysis by nuclear magnetic resonance showed the product to besubstantially pure bis(1,3-dichloroisopropyl) methoxymethanephosphonatewith a refractive index 1.4910 and a density d Example 4 137.5 gm. ofphosphorus trichloride (1 mole) were placed in a flask and thereafter,under cooling, 90 gm. of propylene oxide (1.55 mole) and 66' gm. ofethylene oxide (1.5 mole) were successively added. In this manner amixed 2-chloroethyland 2-chloroisopropylphosphite of the formula P /CHaCHaCI 1.45

was obtai ed.

containing only minor amounts of the corresponding rearrangementproducts (mixture of mixed 2-chloroethyl 2- chloroisopropyl2-chloroethylphosphonate and 2-chloroethyl 2-chloroisopropyl2-chloroisopropylphosphonate) were recovered.

Following distillation under reduced pressure, a product of 93% yield bycomparison to the amount of starting phosphite having the followingelemental analysis was recovered:

O, 18.9% P, 12.1% C1, 28.3%

Analysis by nuclear magnetic resonance showed that the product was amixed methoxymethanephosphonate ester of the formula t /OH: 0-05 with arefractive index n =1A=63 and a density d =1.287.

We claim: 1. Esters of methoxymethanephosphonic acid of the generalformula CHz-O-CHr-P wherein R and R each is an alkyl radical containing2, 3 or 4 carbon atoms substituted at position 2 with at least one atomof bromine or chlorine.

2. A compound according to claim 1 of the formula bis (2-chloroethyl)methoxymethanephosphonate.

3. A compound according to claim 1 of the formula 5 L CH:

bis(2-chloroisopropyl)methoxymethanephosphonate.

. 5 6 4. A compound according to claim 1 of the formula References CitedUNITED STATES PATENTS I" fi 2,934,507 4/1960 Chadwick et a1. 260-950 xCHa-OCH2POCH \cmcl 5 ANTON H. SUTTO, Primary Examiner US. Cl. X.R.

bis 1, 3-dichloroisopropyl methoxymethanephosphonate. 25

1. ESTERS OF METHOXYMETHANEPHOSPHONIC ACID OF THE GENERAL FORMULA